I don't think the LM pose was withdrawn from the BnG set for balance issues. If it was, then Hasbro would've not made Love Letter that pose. They changed the pose of L-I-A-M, but not Love Letter. They also didn't change the poses of Skylark or Pretty Beat, which, if they went to the trouble of changing Twisty Tail, they would surely also have done.

Just because Hasbro UK didn't take every opportunity to eradicate the pose from their lineup, doesn't mean it's not possible they saw some issue with it. The fact remains that they only used it once themselves. And had it removed from four sets they imported from the US. One time by changing a pony, the other times by cutting them out of the sets (the main objective was to reduce the number of ponies, but it's still noteworthy this pose was removed in every instance).

It's important to keep in mind that these decisions are generally not made for a single reason, but for a variety of factors. Also that it can be different people at different times making the decisions. Hasbro might pay the extra cost to have a pony revised in one instance, if they think it will make the pony sell better in their market. In another instance they might not consider the extra cost worth it and just release the set as is.

Mm, honestly I don't think Hasbro UK/Europe as a rule cared much about the rules set down in the original line, because we see them messing around with glittery symbols on earth ponies (Snowflake), no stripe in the unicorn hair (Gypsy) and such very early on. That set also breaks the 2 of each pose rules that were floating around at that time, but still has 2 ponies in the CJ pose (CJ and Snowflake). Though that's another discussion that gets more complicated if you throw in different European releases - my point is that it's not odd to have 2 the same pose, but it's not odd not to

But that set was released before Hasbro stopped making new regular adult molds, and didn't have as many to choose from. It only uses molds copyrighted 1984.

From 1988 and forward the overwhelming majority of regular adult pony sets don't repeat poses within a set. I think Hasbro understood that it's more visually appealing if every pony within a set has a unique pose (when possible), and that it was a deliberate choice.

The only exceptions are:
Brush 'n Grow, because one pony was changed for the european market.
Tales seven characters, likely because there are so many in the set.
Family Friends, because the Shady pose was used to represent the daddies.
Nurse Ponies, possibly because the head was altered with holes to have the nurse hats.
Cookery Ponies, for no apparent reason.

So yeah, I think it sticks out.

What can I say, I really enjoy speculating about what might have been the creative process behind MLP toys. Even farfetched theories are fun to read, and can lead to interesting discoveries in the end.

There's always a risk someone will read speculations and mistake it for a fact. But I think it's better to address it when it actully happens (when something unprovable is claimed as fact), rather than always having to watch your words for fear someone will get the wrong idea. I don't think there should be a line drawn how far people are allowed to speculate.

There are some interesting things about Sweet Delight. I think it's a fair guess she was changed from pegasus to earth because from the schooltime ponies onward Hasbro UK only wanted earth ponies in their adult sets. But even then, why change the symbol from gingerbreads to what she has? And why have her in the same pose as Cherry Sweet, when they clearly had several other earth poses to chose from?

If we assume there was a kitchen playset pony designed which had Sweet Delight's final symbol and pose but a different color scheme, it makes more sense. To save time and money Hasbro could've merged the pegasus prototype with this speculative playset pony, retaining the pink/blue color scheme because it harmonized nicely with the other three. It would also explain why she has an assortment of different baked goods as her symbol (the kitchen came with different ones and tools to make them), which sets her apart from the others. And having the same pose as Cherry Sweet wouldn't be an issue if she originally wasn't intended to be part of the set.

Was this how it happened? Probably not. The true explanation is likely a more simple and boring one, but we'll never know it.

There is no indication that the kitchen was to come with a pony, but I'm thinking about the pink/blue pegasus with gingerbread symbol shown in the 1992 pamphlet, who was replaced with Sweet Delight. Sweet delight has the same color scheme, but a completely different symbol. And her symbol is an assortment of different baked goods, while the others only have one type each. So if we theorize that there was to be a pony included with the kitchen, my guess is that it would've had Sweet Delights symbol, but probably not her color scheme, assuming the protoype pegasus was going to be released as shown.

Although I don't know why they would make them all earth ponies if they were normal ponies.  They don't look like Sweetheart Sisters . . .

That's a good point! They look to be from before Hasbro phased out unicorns/pegasi completely. When the gimmicky sets didn't have a unicorn and/or pegasus there was usually a reason for it (ie the gimmick made horns/wings inconvenient or they were in some specialized mold)

Maybe since they have antennas on top of their heads, also adding a horn to one of them might've been seen as redundant. The lack of pegasi could be because the swirly pattern they were to have all over their bodies wouldn't have worked with, or didn't look good on wings. The existence of the pegasus prototype kind of speaks against this, but maybe that was just a designer grabbing whatever mold they had on hand to get an idea of how the pattern would look on the pony. It looks far from final in any case.

If I've understood correctly, the collector pose was changed mid-year from flat hooves to concave hooves. The first MLP product released was the original set of six, second was the Pretty Parlor with Peachy, and third was the Show Stable with Lemon Drop. Even though collector sites often list them under Year 2, these two playsets belong to the first release year (1983) and were both reissued the year after.

The Pretty Parlor logically must've been released right during the transition from FF to CF, which is why a very, very small number of FF Peachys exist. While the show stable was released after FFs had stopped production entirely, which is why no FF Lemon Drop has been found.

Furbobs! 

Nice catch! I wonder if that graphic might've been part of some clip art collection Hasbro had access to (a lot of the later G2 symbols kind of feel like clip art)? That seems a bit more likely to me than them looking to an obscure european G2 baby to reuse their symbol for a G3.

Then again G2 was still somewhat fresh in memory back then. G3 Sunny Daze pretty much reused G2 Light Heart's color scheme. Petal Blossom exists in both G2 and G3 and is basically the same pony, but could possibly be a coincidence (a purple/pink combination with flower symbol isn't very unique).

I wonder if Hasbro US even was involved with the designs for the later european G2s? It doesn't feel like they were designed by the same people as the ponies from the first few years.